View Full Document


Unformatted text preview:

Expressions of Expertness The Virtuous Circle of Natural Language for Access Control Policy Specification Philip Inglesant M Angela Sasse University College London David Chadwick Lei Lei Shi University of Kent Canterbury UK Symposium On Usable Privacy and Security Carnegie Mellon University 25 July 2008 What do we mean by Expressions of Expertness Need Non security specialists to express access control in formal terms Grid They are experts concerning theircomputing own resources computing similar to cluster they know who should betogether given access to what to linked computers working do which action Systems can be distributed geographically But struggle to express this in formal terms which the administrative computer can interpret Across domains Only the user knows what they really want SOUPS 2008 Page 2 of 14 Access control and authorization Access control is the ability to permit or deny the use of a particular resource by a particular entity Wikipedia AuthZ is more important than AuthN but has been studied less Authorization is inherently complex but for usability complexity is the enemy of success Karat Brodie Karat 2005 SOUPS 2008 Page 3 of 14 The Context of this research PERMIS PERMIS is an integrated AuthZ infrastructure Open source Works with Grid Apache Web servers Net and others PERMIS makes access control decisions as defined by your access control policies written in XML SOUPS 2008 Page 4 of 14 Role Based Access Control RBAC permissions are always Policy positive although there can be specification Actions RBAC permissions are always positive constraints Permissions not Delegated granted are implicitly denied Permissions to do actions on resources are assignment Deny all except assigned to roles Users Roles not users Permissions Assignment of Roles to Users by Administrators User Permission in remote Domains assignment assignment PERMIS allowsmodel you to presents delegate conceptual Resources RBAC difficulties the ability to assign roles to Role

Access the best Study Guides, Lecture Notes and Practice Exams

Loading Unlocking...

Join to view inglesant and access 3M+ class-specific study document.

We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view inglesant and access 3M+ class-specific study document.


By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?